Chaeles h



G. E. SMITH.

Latch.

Patented Mar. 23, 1880;

R U T N E V m WITNESSES.

N- PETE. PIIOTD-LITNOGRAFHER. WASHINGTON. O. C.

UNITED STATES PATENT OFFICE.

CHARLES H. SMITH, OF NEW BRITAIN, CONNECTICUT, ASSIGNOR TO THE RUSSELL &ERWIN MANUFACTURING COMPANY, OF SAME PLACE.

LATCH.

SPECIFICATION forming part of Letters To all whom tt may concern Be itknown that I, CHARLES H. SMITH, of New Britain, in the county ofHartford and State of Connecticut, have invented a new and usefulImprovement in Door-Latches; and I do hereby declare that the followingspecification, taken in connection with the accompanyin g drawings,forming a part of the same, is a full, clear, and exact descriptionthereof. My invention relates to that class of doorlatches known as antifriction latches, in which a lever is employed having a salient facewhich projects beyond the face-plate of the latch, and the office ofwhich is to diminish the friction incident to the working of the latch.

1n latches of this character as usually heretofore constructed thislever has been pivoted to or otherwise directly connected with thelatch-bolt, so that the inward and outward movements of said bolt havebeen directly produced by the movements of said lever.

The present improvement consists in the combination of a lever having aface projecting beyond the face of the door-latch and turned on itspivot by contact with the face of the striker-plate with the mainspring,which operates to project the latch forward into the mortise in thedoor-jamb, so that when the 0 door is closing the resistance of suchmainspring to the sliding of the bolt backward into the latch-case willbe taken ofi' the latch-bolt; and the invention also consists in thecombination, with the sliding latch-bolt, of a spring,

5 the office of which is to act, so soon as the resistance of themainspring is taken off, to retract the latch'bolt.

Referring to the drawings, Figure 1 represents, in side elevation, alatch embodying 40 my improvement, with the cap-plate removed and thebolt in its projected position. Fig. 2 shows a longitudinal section ofthe latch on line a: x of Fig. l and Fig. 3 represents, in perspective,the salientfaced lever, the auxiliary lever engaging it, and theoperative spring. Fig. 4. represents, in side elevation, the frontportion of the latch shown in Fig. 1 having the operative spring of suchproportions and so bent as to render the presence of the auxil- 5o iarylever unnecessary.

Patent No. 225,728, dated March 23, 1880. Application filed December 10,1879.

A is the latch-case, and a the face-plate thereof, which plate ismortised to receive the head 5 of the bolt B and the salient-faced leverC. This lever is pivoted to the faceplate of the latch. and is providedwith a slot,

c, as shown in Fig. 3, which slot is occupied by the end of an auxiliarylever, D, mounted upon a stud, E, projecting from the latch-case.Mounted upon the same stud is the mainspring F, one of whose endsengages alug, d, upon the lever D, the other end engaging a stud, 6,upon the case. Practically, the lever D is a part of the mainspring, asis fully illustrated in Fig. 4:, wherein the lower arm of the spring Fis longer than when used with said 6 lever D, and is extended across theline of the bolt B into the slot 0 of the salient-faced lever C. It hasthe same contact with the bolt and the salient-faced lever that thelever D has, and operates precisely like the shorter spring shown in theother figures, because the lever D operates as a mere extension of thelower springarm. M The spring F operates through the lever D to keep thelever C projected beyond the plane 7 5 of the face-plate a, and alsocauses the lever D to engage the rear of the bolt-head b, as shown inFigs. 1 and 2. The lever D, connected with or forming a member of thespring F, therefore serves to keep the latch-bolt B projected, and also,by its reaction, operates to shoot the bolt outward from the latch-caseafter it has been retracted. In short, if the lever C were removed fromcombination with the mainspring and the latch-case, the constructionremaining would be substantially that of an ordinary door-latch. Fordrawing in the latchbolt there are the usual knob-spindle levers G G,which operate upon the said bolt in a Well-understood manner. 0

It will be observed that the latch-bolt B is furnished with a spiralspring, H, Fig. 2. The office of this spring, which is under tensionwhen the latch-head projects beyond the faceplate, is to shoot the boltinto the latch-case 5 so soon as the superior force of the mainspring,exerted in the opposite direction, is taken off. One end of the spring Hengages a stud, K, upon the latch-case, while the other end of saidspring bears against a depending 10o stud, B, upon the bolt B. The forceof this spring H is less than that of the spring F, so that when thebolt B is in its normal position it is projected, as shown in Figs. 1and 2. When, however, the resistance offered by the mainspring F to therearward movement of the bolt is removed by the action of the lever O,as the result of its face coming into contact with the door-jamb, and ofthe combination of such lever with the mainsprin g, the full force ofthe spring H operates to retreat and house the bolt.

The operation of the latch is as follows: When the door is closing thesalient face of the lever (J comes into contact with the doorjamb andswings the lever D backward, and the bolt B is retracted by the spring Huntil the door is fully closed, and the bolt-head b and lever 0 passinto alignment with the mortises or openings in the striker-plate. \Vhenthe door-jamb no longer furnishes a resistance to the force of thespring F the said spring reacts and, through the lever D, projects thebolt and lever into the striker-plate mortises, and the door is heldfast. In opening the door the knob-levers G G draw back the bolt in theusual manner when the knob is turned, and the lever D is moved backwardin readiness to project the bolt B and lever 0 into their normalpositions when the knob is released.

Although, as above specified, and shown in the drawings, I have providedthe latch with the spring H to retract the bolt, yet the said spring maybe dispensed with, since, upon the lever D being moved backward by thecontact of the lever (l with the door-jamb, no obstruction would bepresented to the retreat of the bolt B within its case, and said retreatwould be produced by the contact of the face of the bolthead with thestriker-plate, and the bolt would afterward be projected into its normalposition when the lever D was allowed to move, as above described. 1t ispreferable, however, to employ the spring H.

Having described my invention, what I claim, and desire to secure byLetters Patent,

1. The combination, substantially as herein described, of the lever O,hinged to the latchcase, with the mainspring of the latchbolt for takingoff lhe resistance of the spring to the backward movement of the boltwhen the door is closing.

2. The combination of the lever O, hinged to the latch-case, themainspring of the latch bolt, the latch-bolt, and a retracting-spring toshoot the bolt into the case when the resistance of the mainspring istaken olf, substantially as described.

CHARLES H. SMITH. Witnesses:

H. E. RUssELL, J r., M. S. VVIARD.

